From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D39F5C47082 for ; Tue, 8 Jun 2021 13:26:00 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 82E686128D for ; Tue, 8 Jun 2021 13:26:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82E686128D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 55C5282BC7; Tue, 8 Jun 2021 13:26:00 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id lOCFbJwdGU-x; Tue, 8 Jun 2021 13:25:59 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp1.osuosl.org (Postfix) with ESMTP id 17FF782CCB; Tue, 8 Jun 2021 13:25:59 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id D53A2C000B; Tue, 8 Jun 2021 13:25:58 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 5732FC0001 for ; Tue, 8 Jun 2021 13:25:57 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 5296D83A84 for ; Tue, 8 Jun 2021 13:25:57 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 4bNDzPZNL00T for ; Tue, 8 Jun 2021 13:25:56 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp1.osuosl.org (Postfix) with ESMTPS id 5E49882BC7 for ; Tue, 8 Jun 2021 13:25:55 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 8A7F3386; Tue, 8 Jun 2021 15:25:53 +0200 (CEST) Date: Tue, 8 Jun 2021 15:25:51 +0200 From: Joerg Roedel To: Peter Zijlstra Subject: Re: [PATCH v3 4/7] x86/sev-es: Run #VC handler in plain IRQ state Message-ID: References: <20210608095439.12668-1-joro@8bytes.org> <20210608095439.12668-5-joro@8bytes.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Cc: kvm@vger.kernel.org, Dave Hansen , virtualization@lists.linux-foundation.org, Arvind Sankar , hpa@zytor.com, Jiri Slaby , x86@kernel.org, David Rientjes , Martin Radev , Tom Lendacky , Joerg Roedel , Kees Cook , Cfir Cohen , linux-coco@lists.linux.dev, Andy Lutomirski , Dan Williams , Juergen Gross , Mike Stunes , Sean Christopherson , linux-kernel@vger.kernel.org, Masami Hiramatsu , Erdem Aktas X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" Hi Peter, On Tue, Jun 08, 2021 at 01:58:47PM +0200, Peter Zijlstra wrote: > So #VC cannot happen with IRQs disabled? > > raw_spin_lock_irq(&my_lock); > <#VC> > raw_spin_lock_irqsave(&my_lock); // whoopsie > > Every exception that can happen with IRQs disabled must be NMI like. > > Again, what you seem to want is to split the handler in a from-user and > from-kernel way, just like we did with #DB and MCE. See how > exc_debug_user() is IRQ-like and can send signals, while > exc_debug_kernel() is NMI like and can not. You are right, thanks for pointing this out. I replaced that patch by one implementing the split in a from-user and from-kernel part. Initial testing looks good, will send it out later this week. Thanks, Joerg _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization